Effect

Frustration inflicts damage and has no secondary effect. The base power of Frustration is dependent on the user's friendship. The lower the user's friendship is, the greater the base power of Frustration. The base power can be calculated using the following formula:

Power = (255 - Friendship) / 2.5

The power of Frustration varies between 1 (at the maximum friendship value of 255) and 102 (at the minimum friendship value of 0). The base power of Frustration is set to 1 if the formula outputs 0. If the user's friendship is 128 or more, Return is stronger than Frustration.

In other games

Frustration does damage depending on the Pokémon's IQ. At no IQ, it does 45 damage. The damage is lowered by 5 after reaching 50 and 100 IQ, and every 100 IQ after that, until it deals 5 damage. Although not possible under normal gameplay, IQ of 1000 or higher makes attack deal 1 damage, while negative IQ makes the attack instantly KO.